New Strategies for Remnant Ear Treatment in Lobule-Type Microtia Reconstruction

An Overview of the Currently Used Congenital Auricular Anomalies (CAA) Classifications for Surgical Reconstruction: A Scoping Review

CAAs are congenital malformations of the auricle ranging from ear underdevelopment to anotia, lacks standardized classification, impacting our outcome of different reconstruction approaches. This scoping review aimed to explore which CAA classifications are most used in current ear reconstruction practices.

We conducted a scoping review following the PRISMA guidelines, searching MEDLINE and Embase databases on November 1st, 2023. Studies on CAA reconstruction that included clear descriptions of the used classification published in the past 5 years were included. Studies were appraised using the Joanna Briggs Institute checklist.

Out of 293 screened studies, 45 met inclusion criteria, encompassing 19 case series and 5 cohort studies. Findings revealed a predominant use of the Nagata classification across rib cartilage and alloplastic material reconstructions, despite noted application inconsistencies. Other systems like Marx's, Weerda's, and Meurman's remain underutilized.

Most studies used the Nagata's classification. Its widespread use underscores the necessity for an easy to use, but standardized classification to improve surgical outcome reporting and assessment accuracy. Further investigation and standardization efforts regarding the Nagata system are recommended.

Advances in the Development of Auricular Cartilage Bioimplants

Conditions such as congenital abnormalities, cancer, infections, and trauma can severely impact the integrity of the auricular cartilage, resulting in the need for a replacement structure. Current implants, carved from the patient's rib, involve multiple surgeries and carry risks of adverse events such as contamination, rejection, and reabsorption. Tissue engineering aims to develop lifelong auricular bioimplants using different methods, different cell types, growth factors and maintenance media formulations, and scaffolding materials compatible with the host. This review aims to examine the progress in auricular bioengineering, focusing on improvements derived from in vivo models and clinical trials, as well as the author's suggestions to enhance the methods. For this scope review, 30 articles were retrieved through Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, plus 6 manually selected articles. The methods reported in the articles were categorized into four levels according to the development phases: source of cells, cell media supplementation, scaffold, or scaffold-free methods, and experimental in vivo or clinical approaches. Many methods have demonstrated potential for the development of bioimplants; four clinical trials reported a structure like the external ear that could be maintained after overcoming post-transplant inflammation. However, several challenges must be solved, such as obtaining a structure that accurately replicates the shape and size of the patient's healthy contralateral auricle and improvements to avoid immunological rejection and resorption of the bioimplant.

New Strategies for Remnant Ear Treatment in Microtia Reconstruction Based on Morphometric Studies

OBJECTIVE

Given the lack of specific evaluation indices, it is difficult to determine whether to transpose or abandon remnant ears in lobule-type microtia reconstruction. The authors illuminate referable parameters beneficial for proper treatment of remnant ear in an efficient manner.

METHODS

A series of 359 lobule-type microtia patients underwent autogenous costal cartilage auricular reconstruction between 2016 and 2021. Fourteen measuring points and defined distances as well as six ratios of specific distances based on position, plumpness, similarity and the width-to-length ratio of the remnant ear have been described, and relevant tactics for appropriate treatments are introduced.

RESULTS

Definite morphometric results contribute to attaining satisfactory contours of reconstructed auricles with harmonious earlobes, which exhibit highly similar dimensions and appearances compared to the contralateral normal ears.

CONCLUSION

With the help of the proposed locating points and measuring approaches, the procedure of remnant ear treatment is systematically clarified. This technique ensures operation safety and contributes to the aesthetic contour of the auricle.

LEVEL OF EVIDENCE

IV Laryngoscope, 134:2741-2747, 2024.

Exploring Aesthetic Outcomes and Complications in Auricular Reconstruction Utilising Autologous Cartilage: A Systematic Review and Narrative Synthesis

Auricular reconstruction remains a challenging procedure, requiring a high degree of manual dexterity and attention to detail in order to reconstruct the complex three-dimensional geometry of the ear successfully. Most techniques will rely on autologous cartilage for auricular framework fabrication, carrying a risk of donor and recipient site morbidity. The aim of this report is to investigate the complications and aesthetic outcomes associated with autologous cartilage harvest in auricular reconstruction. A systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) and reported in accordance with the Preferred Reporting for Items for Systematic Reviews and Meta-Analyses. Comprehensive electronic search strategies for four databases were developed. Studies were screened according to the inclusion and exclusion criteria by two independent reviewers. The literature search identified 7171 articles. Filtering for relevance and duplication reduced the number of articles to 52. A total of 12,215 patients underwent auricular reconstruction utilising autologous cartilage. Indications included 11,696 patients due to microtia, 334 patients due to burns or trauma, 70 patients due to constricted ears, and 115 patients due to prominent ears. The most commonly reported donor site complications included chest wall deformities (n = 159). The most commonly reported recipient site complications included hypertrophic or keloid scars (n = 279), haematoma (n = 155), tissue expander exposure (n = 111), cartilage or framework exposure (n = 122), and cartilage framework deformation or resorption (n = 50). Although a challenging procedure, auricular reconstruction utilising autologous cartilage is possible. Exceptional aesthetic results can be achieved when performed by a skilled surgeon on appropriately selected individuals. However, the potential risks and complications associated with the procedure should be discussed with the patient and family beforehand.

Microtia Part I: Preoperation and In-operation Lessons from 1012 Ear Reconstruction Operations

BACKGROUND

Organ reconstruction is one of the most challenging tasks in plastic and reconstructive surgery. This is particularly true of ear reconstruction, which requires enormous attention to detail.

METHODS

In the first of two articles, we set out details and precautions for each step of the preoperative and intraoperative stages of the ear reconstruction process for microtia patients. We cover preoperative screening and assessment of surgical conditions, the design of intraoperative incisions, flap separations, costal cartilage extraction, framework carving and cranial ear angle surgery.

RESULTS

Over the period Jan 2015-July 2021, our surgical team carried out 1012 microtia ear reconstructions, at the rate of 3-4 per week. This article presents the key learnings from this high volume of operations. Two typical cases involving different types of microtia are presented in order to illustrate the process of total ear reconstruction.

CONCLUSIONS

This article describes in detail the preoperative and intraoperative stages of the ear reconstruction process. We share our cumulative surgical experience gained over 20 years, especially the latest practical lessons gleaned over the last six and a half years.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Strategies for the Treatment of Auricular Complications after the First Stage of Autologous Cartilage Microtia Reconstruction

BACKGROUND

Effective handling of auricular complications after the first stage of autologous cartilage microtia reconstruction remains one of the most demanding challenges for plastic surgeons. Here, the authors discuss relevant details for treatment of such complications in various conditions.

METHODS

A total of 1739 microtia patients underwent the first stage of auricular reconstruction with autogenous costal cartilage between 2007 and 2019. Different complications occurred in 136 cases. The details of complications are described, and relevant tactics for appropriate prevention and treatment are introduced.

RESULTS

Selective methods for the management of different complications in a prompt and effective manner after the first stage of ear reconstruction have been shown to salvage and maintain the contour of the reconstructed auricle to the maximum extent.

CONCLUSION

Auricular complications can be well treated and prevented through careful preoperative preparation, meticulous intraoperative manipulation, and proper postoperative management.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

A novel method to accurately locate the reconstructed auricle

BACKGROUND

Congenital microtia is a common congenital disease in children, the cause of which is still unclear. At present, the main treatment for congenital microtia is ear reconstruction. Accurately locating of the reconstructed ear on the affected side before ear reconstruction surgery is difficult, while it is the key of successful operation. Our ear reconstruction team has developed a novel method to accurately locate the reconstructed auricle. This novel method has achieved good results in clinical practice.

METHODS

Thirty patients with unilateral ear reconstruction, who underwent auricle reconstruction using our invented auricle reconstruction positioning method in the Plastic Surgery Hospital of Chinese Academy of Medical Sciences from January 2020 to July 2021, were enrolled in this study.

RESULTS

Through Wilcoxon signed rank test, we found that there was no statistical difference between the mean distance from the highest point of the patient's normal ear to the central axis of the nose and that from the highest point of the reconstructed ear to the central axis of the nose (P>0.05). Meanwhile, there was no statistical difference between the mean distance from the lowest point of the patient's normal ear to the central axis of the nose and that from the lowest point of the reconstructed ear to the central axis of the nose (P>0.05). The satisfaction rate of patients and their families to the location of the reconstructed auricle was 100%.

CONCLUSIONS

The novel method of locating the reconstructed auricle employs simple materials. The implementation process is easy, and the effect is significant. To a certain extent, it solves the difficulty of locating the reconstructed auricle in ear reconstruction operation. Although this method can only be applied to patients with unilateral microtia, we recommend it for locating the reconstructed auricle by every plastic surgeon.

New strategies for base frame fabrication in microtia reconstruction

The base frame provides a stable support for the helix, antihelix, and tragus–antitragus complex in microtia reconstruction, and this support is vital to attain a highly defined outline for a reconstructed auricle. The success of base frame sculpting depends on appropriate treatment of the cartilage, mainly the sixth and seventh costal cartilages, which may have different characteristics. The aim of this study was to demonstrate the relevant details for base frame fabrication under various scenarios. Between 2016 and 2019, a total of 352 patients with microtia underwent autologous auricular reconstruction. Concerning the different sizes and characteristics of the costal cartilage used for the base frame reconstruction, we describe the related methods for fabrication and introduce corresponding strategies for proper management. We found that 90% of the patients responded at follow-up, and 76% of them were satisfied with the cosmetically refined auricle with harmonious integrity. The elaborate design and appropriate utilization of costal cartilage for base frame sculpting is one of the most significant and fundamental processes in microtia reconstruction. It contributes to achieving a clearly defined outline of the auricle with harmonious integrity, which is as important as the other projected subunits.